Air washer



Oct. 22, 1957 R. J. LOFQUIST ETAL 2,810,481

AIR WASHER Filed Oct. 8, 1956 4 Sheets-Sheet l P a o M m s 9 s 2 s d 3 1 E m2 OOOOO r z z Z Z m INVENTOR. RALPH J- LOFQUiT 'EMERY G. MlLUGAN ATTCDZNEY Oct. 22, 1957 R. J. LOFQUIST ETAL 2,810,481

AIR WASHER 4 Sheets-Sheet 2 Filed Oct. 8, 1956 INVENTOR. RALPH J- LOFQUIT 'EMERY O. MILLlGAN AT TO RNEY Oct. 22, 1957 R. J. LOFQUIST ETAL 2,810,481

AIR WASHER Filed Oct. 8, 1956 4 Sheets-Sheet 5 /5O INVENTOR. .4 RALPH J. LoFQuleT 'EMERYCZ MILLIGAN W Z-A Oct. 22, 1957 R. J. LOFQUIST El'AL 2,8

AIR WASHER Filed Oct. 8, 1956 4 ShGGtS-ShGGt 4 nvwzzvrozm RALPH J. LoF ule'r EMEKY O. M\LL\GAN Uniwd S tes Patent towel AIR WASHER Ralph J. Lofquist, Chicago, and Emery 0. Milligan, West Frankfort, 11]., assignors to Elem Corporation, Chicago, 111., a corporation of Illinois Application October 8, 1956, Serial No. 614,549

12 Claims. (Cl. 269-466) This invention relates to improvements in air washers for coal and the like and more particularly relates to such washers which operate on the suction principle.

A principal object of the invention is to provide a simpler and more economical air washer for separating refuse from coal and the like by suction.

Another object of the invention is to provide a novel and economical air washer for coal and the like in which the separation of refuse from the coal is solely by drawing air through a vibrating bed of refuse and coal by suction and in which coal is drawn off the top of the refuse and the refuse and coal are automatically discharged in accordance with the weight thereof.

A further object of the invention is to provide an air washer for coal and the like in which the coal is passed over a vibrating screen having spaced barriers extending laterally thereof at regular intervals to build up a bed of coarse refuse on the screen and in which air is drawn through the screen and bed of refuse by suction to separate the coal therefrom.

A still further object of the invention is to provide a vibrating screen in which the screen is formed from wire or rods having a plurality of loops extending upwardly from the surface thereof and forming a means for attaching the screen to its frame and also forming barriers to effect the building up of a bed of coarse refuse on the screen.

A still further object of the invention is to provide an improved form of screen for coal and the like in which the drive to the screen is through the center of gravity thereof.

These and other objects of the invention will appear from time to time as the following specification proceeds and with reference to the accompanying drawings wherein:

Figure l is a view in side elevation of an air cleaner constructed in accordance with the invention;

Figure 2 is a longitudinal sectional View taken through the cleaner shown in Figure 1;

Figure 3 is a fragmentary detail view of the deck, screen and air valve, with certain parts of the air valve shown in transverse section;

Figure 4 is a fragmentary sectional view taken substantially along line IV-IV of Figure 3;

Figure 5 is a fragmentary plan view of the screen and deck;

Figure 6 is a fragmentary longitudinal sectional view taken through the screen and air valve; and

Figure 7 is an enlarged detail view of a portion of the screen illustrating the resilient spacers between the wires of the screen.

In the embodiment of the invention illustrated in the drawings, 10 designates a suction air cleaner constructed in accordance with the invention and having a vibrating deck 11 extending for substantially the length thereof and supported adjacent the entering end of the cleaner on a pedestal 12 and vibrating deck support block 13, suit- Patented Oct. 22,- 1957 ECQ ably mounted on said pedestal and supporting the entering end portion of the deck 11 thereon. The vibrating support block 13 may be made from rubber, an elastomer or like material bonded to a plate 15, bolted or otherwise secured to the top of the pedestal 12 and bonded to a bottom plate 16, forming the hutch deck of the vibrating deck.

The vibrating deck 11 is supported at its end opposite the vibrating support block 13 on a plurality of yieldable deck supports 17, which like the vibrating deck support 13 may be made from rubber an elastomer or like material and which form flexible partitions and seals for a refuse chute 19 and a clean coal chute 20. As herein shown, the supports and seals are supported on walls 21, 22 and 23 of the chutes 19 and 20, andform vibrating supports for uper walls 24, 25 and 26 respectively of said chutes and vibrating deck, and cooperate with the vibrating deck support 13 to support the entire deck and upper portions of the chutes therefor for vibratory movement in a horizontal plane.

The deck 11 is shown as vibrated by means of an eccentric counterweight type of vibrating unit 27 which may be of any well known form and which is connected with the deck 11 intermediate the ends thereof and adjacent the center gravity thereof. As herein shown, spaced brackets 29 are secured to opposite side walls 30 of the deck 11 and depend therefrom and have a transverse shaft 31 journaled therein counterweighted eccentric of the center thereof and having a drive pulley 33' thereon. A motor 35, mounted on a base 36 for the frame structure for the cleaner is shown as driving the pulley 33 and vibrating unit through a belt 37.

The deck 11 including the hutch deck formed by the bottom plate 16 is a sealed unit and the side walls 30 thereof extend upwardly therefrom for the full length thereof from a hopper-like receiving end portion 39, disposed beneath a raw coal chute 40, to the wall 26 of the clean coal chute 20. The deck 11 is sealed to a suction hood 41, extending from the raw coal chute 40' for-the entire length of said deck, by a flexible seal 43 extending about the upper end portion of said deck and retained thereto as by retainer straps 44 extending thereabout. The flexible seal 43 also extends about the hood 41 and rear end portion of the chute 40 and is retained thereto as by straps 45 extending thereabout.

The raw coal chute 40 is sealed by a valve 46, herein shown as being a butterfly type of valve mounted on a pivot shaft 47 and having an arm 49 extending outwardly therefrom, which may be counterweighted to maintain the valve'closed by gravity. As herein shown, the arm 49 has a pin 50 extending inwardly therefrom guided along an arcuate slot 51 formed in a sector 53 secured to the outer wall of the hood 41. The pin 50 may be turned by a wrench, or the like, to positively retain the valve 46 in an open or closed position, if desired.

The refuse discharge chute 19 and the clean coal discharge chute 20 are sealed by vertically spaced valves 55, 55 and 56, 56 respectively, which are also counterweighted to maintain the valves closed but to accommodate the valves to open as a predetermined weight of refuse and coal is discharged onto the respective valves.

The valves 55 are each shown as being mounted on a separate transverse shaft 57 pivotally mounted in opposite side walls 59 of the frame structure for the cleaner and extending outwardly through a cover plate 60 in one of said side walls. The arm 61 is mounted on the end of the shaft 57 and has a counterweight 63 adjust'ably carried thereon and retained in'position on said arm as by nuts 64. In asimilar manner each valve 56 is mounted on a transve'rseshaft 58 having a counterweighted arm 65 thereon' The valves 55, 55 and 56, 56 are thus normally closed except when the weight of refuse and of coal on the respective valves is sufiicient to open said valves. The coal and refuse may thus be withdrawn automatically with no attention from the operator of the device.

The hood 41 is divided into three suction sections 66, 67 and 68 having partitions 69, 70 and 71 respectively extending downwardly therefrom to the top of the side plates of the deck 11. The sections 66, 67 and 68 have suction ducts 73, 74 and 75 respectively, leading upwardly therefrom and connected with a common duct 76, connected with a source of vacuum such as a suction blower (not shown). The amount of suction provided is sufiicient to keep the fine coal particles from filtering down through the deck, the amount of suction in each hood section 66, 67 and 68 being controlled by butterfly valves 79, 80 and 81' in the respective ducts 73, 74 and 75.

The deck 11 has a screen 83 extending along the top surface thereof and shown as being formed from looped wires or rods, herein shown as being wedge-shaped in cross-section, with the smaller end of the wedge facing downwardly and looped in a plurality of equally spaced places spaced therealong to form a plurality of loops 85 through which support bolts or rods 86 extend, for mounting the looped wires between side plates 87 of the screen in side by side relation with respect to each other, as shown in Figure 3. As herein shown the loops of the looped wires extend upwardly from the screen portion thereof to provide a plurality of equally spaced laterally extending barriers or ribs extending upwardly from the surface of the screen to retain the heavier refuse to the surface of the screen and fill the space between the loops or barriers with coarse refuse which will let the fine refuse particles filter through to the top of the plate 16 forming the hutch deck and will retain the clean coal from joining the refuse flowing through the screen deck.

The looped wires or rods 85 are spaced apart on the rods 86 by washers 88, which may be coned disk springs or like resilient spacers, which will open up the space between the wires upon the loosening of retainer nuts 89 threaded on the ends of the rods 86' and abutting the side frame members 87 of the screen. The minimum spacing between the wires or rods may be .04 of an inch while the'spacing between the rods should'be capable of being 7 bonded to cylindrical housings 93 for air valves 94. The

cylindrical housings 93 are spaced along the strip 11 between the side plates 30 thereof and-between .the bottom of the screen 83 and the plate 16 forming the hutch deck, and serve as supports-for the buffer strips 91 and the screen 83, and also serve as a means for admitting air from the atmosphere to be drawn up through the screen 83 from the bottom thereof. The 'buder strips 91 may be made from rubber or a like material and serve as partitions to accommodate the drawing of airupwardly along each side thereof, as well as yieldablesupports for the screen 83. The screen 83 is retained from vertical movement with respect to the supporting buffer strips 91. by

thehorizontal legs of angles 92 secured to the inside of the side. frame members 30 and extending therealong for the length of the screen.

Each cylindrical housing 93 has a plurality of aligned spaced port openings 95 opening through the wall thereof on opposite sides of the buffer strip 91 in the upper half of said housing and facing the bottom of the screen 83. The port openings 95 on one side of the buifer strip 91 are; shown in Figure 4v as being staggered with respect to; the, port openings, 95, on the opposite sideof saidbuffer strip Eachl valve 94..is shown assbeing inthe form of 4 a pipe or tube 96, extending within the housing 95 for rotatable adjustable movement with respect thereto. Each tube 96 is provided with a plurality of port openings 99 on each side of a vertical plane extending through the center thereof and registerable with the port openings 95 on each side of the buffer strip 91. Two tubes 96 may be provided in each housing 93, each extending within said housing from the outer end thereof and joining at the center thereof. The individual tubes 96 are adjustable from the side walls 30 on the outside thereof, to accommodate the air intake on each side of the longitudinal center of the screen 83 to be varied if desired. As herein shown, each tube 96 has an annular plate 100 welded or otherwise secured thereto and extending outwardly therefrom adjacent the outer end thereof. Each plate 100 abuts the outside of an associated side wall 30 and is apertured as indicated by reference character 97 to afford a means to be engaged by a spanner wrench for turning said plate and the associated valve as desired, until the correct air intake is attained on each side of the center of the screen 83. The tubes 96 and plates 100 may be retained in position by clamps 101 secured to the walls 30 and clamped into engagement with the outer faces of the plates 100. Turning movement of the tubes 96 to a position which would block off the supply of air to the screen is prevented by abutment surfaces 103 engageable with the clamps 101.

At the discharge end of the vibrating deck is a cutting plate 106, which may be mounted between the side walls 30 of the deck and which has a cutting edge 107 extending across the deck in vertically spaced relation with respect thereto and cutting the coal from the heavier refuse discharging into the refuse chute 19. The cutting plate 106 may be adjustably mounted in the side walls 30 to permit the cutting edge to be raised and lowered with respect to the deck to suit the coal being cleaned, it being understood that when the cutting edge 107 is once properly adjusted to the proper height for a certain grade of coal that it may be fixed in position as long as coal of the same grade is being cleaned.

In operation of the device, assuming the valves 94 on each side of the deck have been properly adjusted for the required air intake to keep the coal particles from filtering down through the refuse on the screen 83 and through the screen, and that the cutting plate has been adjusted for the grade of coal to be cleaned, the motor 35 is startcd'to bring the entire deck into vibratory motion. Raw coal'is then admitted through the raw coal chute 40 under the control of the valve 46 from which it drops onto the hopper 39. At the same time air is drawn in through the valves 96 and screen 83 and exhausted through the hood sections 66, 67 and 68 under control of the valves 79, and 81 by suction in said hood sections. During progress of the raw coal along the screen 83, the refuse will build up between the barriers or ribs formed by the loops and fine refuse will pass down through the screen onto the hutch deck 16, the air drawn upwardly through the ports on each side of the partitions 91 suspending the fine coal and prevently particles thereof from filtering down through the screen.

The coal discharged from the chute 40 onto the hopper 39will then progress along the vibratory screen 83, the heavy refuse such as rock and the. likesettling on the screen 83 or between the barriers or ribs 85 and forming a filter bed alongwhich the lighter coal moves, and preventing the finer clean vcoal from joining the refuse dropping through the screen. Atthe discharge end of the screen, the heavy refuse will flow down through the refuse chute 19 joining, the fine refuse flowing along.

the hutch deck and dischargedby gravity under the control of the counterweighted valves 55, 55'. The lighter coal flowing along the top of the refuse bed'and being partially suspended thereonby the air drawn" through the deck will be cut off from the refuse by the cutting edge 107 of the cutting plate 106 to drop throughthe chutei 20 for discharge under the control of the counterweighted valves 56, 56.

It is of course understood that a variation in suction along the screen 83 may be obtained by adjustment of the butterfly valve 79, 8t) and 81 and that the counterweighted valves 55, 55 and 56, 56 may be so weighted as to accommodate the refuse and coal to build up on the vibrating screen 83 to the most efficient level for separating the coal from the refuse, by the drawing of air therethrough under suction.

It should further be understood that in a complete machine, the deck 76 may be connected with a cyclone separator (not shown) to separate the dust from the air.

It will be understood that modifications and variations in the present invention may be effected without departing from the spirit and scope of the novel concepts thereof.

We claim as our invention:

1. In an air cleaning apparatus for coal and the like, a vibrating deck having an upper screen deck and a lower hutch deck, means for vibrating said deck, separate refuse and clean coal chutes at the discharge ends of said decks, a cut-off plate at the discharge end of said screen deck for cutting off the clean coal from the refuse to flow down said coal chute, and accommodating the refuse to flow down said refuse chute by gravity, a plurality of air inlets in the space between said hutch deck and said screen deck and extending across and spaced along said screen deck to direct air through the bottom thereof at various points therealong without interferring with refuse on said hutch deck, said air inlets having communication with a source of air at atmospheric pressure, and a hood extending across the top of said screen deck and sealed thereto and having connection with a source of suction for drawing air through said air inlets up through said screen for substantially the length thereof.

2. In an apparatus for cleaning coal and the like, a vibrating deck having an upper screen deck and a lower hutch deck, means for vibrating said deck, a hood extending over the top of said deck for substantially the length thereof, means for sealing said hood to said deck, said hood having connection with a source of suction for drawing air through said screen deck by suction, a raw coal chute at one end of said screen for admitting raw coal thereto, valve means sealing said chute and controlling the How of raw coal onto said screen, a refuse chute having communication with said screen deck and said hutch deck for conducting refuse therefrom, valve means sealing said refuse chute and controlling the flow of refuse therefrom, a clean coal chute spaced forwardly of said refuse chute, a cut-off plate extending from said clean coal chute over said refuse chute and having a cutting edge spaced in vertical relation with respect to said screen and cutting ofl the clean coal from the refuse on said screen, a plurality of air valves extending across said screen in the space between said screen deck and said hutch deck for admitting air to said screen to pass therethrough from the bottom thereof, and means for adjusting said valves to effect the drawing of the required quantity of air through said screen to suspend the fine particles of coal passing therealong.

3. In an air cleaning apparatus for coal and the like, a vibrating deck having an upper screen deck and a lower hutch deck, means for vibrating said deck, a hood adapted to be connected with a source of vacuum extending over the top from said screen deck and sealed thereto, a plurality of air intake valves spaced along the bottom of said screen deck and above said hutch deck and having communication with a source of air at atmospheric pressure for providing a uniform supply of air to the bottom of said screen deck without disturbing the refuse on said hutch deck, said air intake valves being adjustable at the selection of the operator to selectively vary the'qu'antity of air drawn through said screen deck by suction.

4. In an apparatus for cleaning coal, a vibrating deck having a screen deck and a hutch deck for refuse extending thereoeneath and having side walls connecting said decks together, a chute for discharging raw coal onto said deck and screen, refuse and clean coal chutes at the discharge end of said screen for separately receiving refuse and clean coal by gravity, means for vibrating said screen, means for admitting air at atmospheric pressure to the underside of said screen for substantially the length thereof comprising a plurality of valves spaced along said screen in the space between said hutch deck and screen and having housings extending across said side walls and opening to the outsides thereof, having ports therein opening to said screen, and tubular valves rotatably mounted within said housings and having ports corresponding to the ports therein for varying the flow area of said ports upon adjustable turning movement of said valves with respect to said housing.

5. In an apparatus for cleaning and the like, a Vibrating deck having a screen deck extending therealong and having a hutch deck spaced beneath said screen deck for the conveying of refuse, a chute for discharging raw coal onto said screen deck adjacent the entering end thereof, refuse and clean coal chutes at the opposite end to said screen for separately receiving refuse and clean coal by gravity, means for vibrating said screen having driving connection therewith adjacent the center of gravity thereof, a plurality of air valves in the space between said hutch deck and screen comprising a plurality of housings extending beneath the bottom of said screen and mounted in said side walls at the ends thereof and spaced along said screen for substantially the length thereof, flexible supports extending along said housings and supporting said screen thereon, ports in said housings on opposite sides of said flexible supports and facing said screen, tubular valves extending within said housings from opposite ends thereof and opening to the outside of said side walls, each of said tubular valves having ports therein corresponding to the ports in said housings, means accommodating adjustment of said tubular valves with respect to said housings to vary the flow area of said ports in said housings, and a hood extending along the top of said screen and sealed thereto and adapted to have connection with a source of air under suction for drawing air through said valves and screen.

6. In an apparatus for cleaning coal and the like, a vibrating deck having an upper screen deck and a lower hutch deck and side walls connecting said decks together, a hood extending over the top of said screen deck and sealed thereto, a raw coal chute at the entering end of said screen deck, valve means sealing said chute and accommodating the passage of raw coal through on said screen, refuse and clean coal chutes at the end of said screen for receiving refuse from said screen and hutch deck by gravity, a cutting plate extending from said clean coal chute and having a cutting edge disposed above said screen for separating the clean coal from the refuse to fiow down-said clean coal chute,

counterweighted valves in said refuse and clean coal said housings and facing said screen on opposite sides of the vertical center lines of said housings, yieldable buffer strips supporting said screen deck on said hous ings, tubular valves extending within said housings from opposite ends thereof toward the center thereof and opening to the outside of said side walls for cornmunication with a source of air at atmospheric pressure, said 7 tubular valves each having ports therein corresponding to the ports in said housings and being turnable to vary the cross-sectional area of the ports in saidhousings and the intake of air through said screen. 1

7. In an apparatus for cleaning coal and the like, a vibrating deck having a screen extending therealong and having parallel spaced side plates at opposite sides of said deck, a plurality of wires-extending along said deck and looped at regular intervals, rods extending across the side plates of said deck through the looped portions of said wires and supporting said wires with the looped portions extending upwardly therefrom to form barriers extending transversely across said screen at regular intervals, to effect the building up of coarse refuse on said screen, accommodating the finer particles of refuse to filter therethrough, yieldable spacers on said rods and separating said wires, nuts'on the ends-of said rods for compressing said spacers and restricting the spaces between said wires, and turnable toaccommodate said spacers to separate said wires and vary the spacing therebetween.

8. A vibrating screen comprising a generally rectangular frame having a plurality of parallel spaced wires extending along said frame from one end thereof to the other and having aligned loops formed therein at regularly spaced intervals and facing upwardly with respect to said wires, cross rods extending across said frame through said loops for supporting said wires thereto, nuts on the ends of said cross rods retaining said wires in spaced relation with respect to each other, and yieldable spacers on said rods between the loops of said wires for separating said wires upon loosening of said nuts and varying the spacing therebetween.

9. A vibrating screen comprising a generally rectangular frame having a plurality of parallel spaced wires extending along said frame from one end thereof to the other and having aligned loops formed therein at regularly spaced intervals and facing upwardly with respect to said wires, cross rods extending across said frame through said loops for supporting said wires thereto, yieldable spacers on said rods between said wires, fastening means on the ends of said cross rods retaining said wires in spaced relation with respect to each other and operable to compress said spacers and vary the spacing between said wires, a plurality of housings extending across said frame in parallel spaced relation with. respect to each other and having ports leading therethrough for the admission of air to the bottom of said screen, and yieldable butter strips extending upwardly from said housings and supporting said screen on said housing.

' 10. A vibrating screen comprising a generally rectangular frame having a plurality of parallel spaced'wires.

extending along said frame from one end thereof to the other and having aligned loops formed therein at regularly spaced intervals and facing upwardly with respect to said wires, cross rods extending across said frame through said loops for supporting said wires on said frame, nuts on the ends of said cross rods retaining said wires in spaced relation with respect to each other, a plurality of housings extending across said frame in parallelspaced relation-with respect toeach other and having ports leading therethroughfor the admission of air to the bottom of said screen, yieldable buffer strips extendingupwardly from saidhousing and supporting said screen thereon, and yieldable-spacers on said rods between'the loops of said looped wires, for separating said wires upon loosening of said nuts and varying the spacing therebetween.

1 1.v A vibrating deck having a screen deck and a hutch deck spaced therebeneath, means for vibrating said deck and having drive connection therewith adjacent the center of gravity thereof, side plates connecting said screen and hutch decks together, a plurality of equally spaced laterally extending air inlet housings extending across said side plates between said screen deck and said hutch deck and opening to the outsides of said plates and having ports leading through the walls of said housings directed toward the bottom of said screen deck for admitting air to said screen deck to flow through the bottom thereof, said screen deckcomprising a generally rectangular frame having a plurality of parallel spaced wires extending therealong from one end thereof to the other and having aligned loops formed therein at regularlyspaced intervals and extending upwardly from said wires, cross rods extending through said loops and frame for supporting said wires on said frame, means supporting said screen between said side plates comprising yieldable buffer strips extending across said housing and extending upwardly therefrom and having supporting engagement with said wires, and retainers extending along said side plates above said screen and retaining said screenv to said buffer strips.

12. In an apparatus for cleaning coal by air, a vibrating. deck having an upper screen deck and a lower hutch deck for refuse extending beneath said screen deck and having side walls connecting said decks together, a hood extending over the top of said screen deck and sealed thereto and. adapted to be connected with a source of vacuum for drawing air through said screen deck, means for vibrating said decks, means for admitting air at atmospheric pressure to the underside of said screen deck comprising a plurality of valves extending transversely of said screen deck in the space between said screen deck and said hutch deck and including cylindrical housings extending across said side walls and opening to the outsides thereof and having ports therein opening to the bottom of said screendeck, and cylindrical valves rotatably mounted within said housings and opening to the outer .ends thereof and having ports corresponding to the ports in said housings for varying the flow areas of the ports in said housings upon adjustable turning movement of said valves with respect to said housings.

References Cited in the file of this patent UNITED STATES PATENTS 1,400,697 Seivour Dec. 20, 1921 2,068,783 Wendall Jan. 26, 1937 2,161,500 Bird et a1 June 6, 1939 

